1. Field of the Invention
The present invention relates to microscopes adapted primarily for surgical procedures, more particularly to, microscopes having two viewing stations.
2. Description of Related Art 2.
In the practice of ophthalmology, assistant surgeons, nurses, students, and other technical personnel are involved with the primary surgeon during the performance of surgical procedures upon the eye, or upon any other generally relatively flat surface or tissue to be treated. As a result, a particular image must be observed by the primary surgeon and the assistant with a single microscope.
Referring to FIG. 1, an example of a microscope system to observe an image by the primary surgeon and assistant is shown. This microscope system consists of two independent microscopes with identical optical axes below a common beam splitter 1. The primary surgeon views the image through the main microscope 2 which passes through the common beam splitter 1. The assistant views the image through the assistant's microscope 3 which passes through the common beam splitter 1 and an internal focus 4. The image is reflected by mirror 5 and passes through the 3-step magnification changer 6 in the tube 7 of the assistant's microscope 3.
One disadvantage with the above microscope system is that a beam or ray of light must be split by a beam splitter. This results in a greater light loss to both the primary surgeon and the assistant. Another disadvantage is that the ray of light to the assistant is reflected by mirrors. This prevents the assistant from manipulating his binocular so that it is always parallel to the image when the microscope is at an oblique angle to the image. Otherwise, there would be a view angle difference.
It is, therefore, one object of the present invention to provide a microscope system which allows a primary and secondary observer to simultaneously view the same image.
It is another object of the present invention to provide at least two station viewing without the use of beam splitters or mirrors.
It is a further object of the present invention to allow the secondary observer to manipulate its binocular so that the binocular is always parallel to the image while the microscope is at an oblique angle to the image.